The HiLumi LHC Design Study (a sub-system of HL-LHC) is co-funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement QXF Cross-section, Cable Winding Test, End Parts Design, Support Structure Franck Borgnolutti, Miao Yu, Susana Izquiero Bermudez, Helene Felice, Paolo Ferracin 11/15/2012

QXF overview 150 mm aperture 140 T/m nominal gradient Support structure based on aluminum shell pre- loaded with bladders Status of the development – Conductor and cable R&D – Magnetic and mechanical design and analysis 15/11/2012 G. Ambrosio and P. Ferracin2

Cable R&D Winding test in progress at FNAL, LBNL and CERN Goal – determine mechanical stability of the cable during winding – Provide feed-backs for cable optimization 15/11/2012 G. Ambrosio and P. Ferracin3

Coil design Preliminary cross-section Different cross- sections considered 15/11/2012 G. Ambrosio and P. Ferracin4 Units Gradient T/m 140 Nominal Current kA Fraction of Iss% Temp. MarginK Peak InT Stored InMJ/m Diff. inductancemH/m Nb turn/coil Lorentz stressMPa-110/ / /-126

Coil design End region Different programs (BEND, Roxie) compared Design of winding pole and end spacers on going 15/11/2012 G. Ambrosio and P. Ferracin5 0.3 mm

Support structure Preliminary 2D mechanical analysis completed Criteria to evaluate different designs determined – The baseline structure is capable of provide support up to 90 % of I ss 15/11/2012 G. Ambrosio and P. Ferracin6

Radiation Resistance G. Ambrosio Fermilab 2nd Joint HiLumi LHC/LARP Annual Meeting November, 2012 Frascati Work supported by the US LHC Accelerator Research Program (LARP) through US Department of Energy contracts DE-AC02-07CH11359, DE-AC02-98CH10886, DE-AC02-05CH11231, and DE-AC02-76SF00515 The HiLumi LHC Design Study is included in the High Luminosity LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement Inspired by discussions with G. De Rijk, A. Ghosh, E. Fornasiere, R. Flukiger, P. Fessia, S. Canfer and many other people

Requirements Lots of good work is being done Now is time to set MQXF requirements: – Shear strength (measurement technique and value) Different measurement techniques give very different results – Thermal conductivity – Minimum RRR before warm up – Maximum swelling before warm up 15/11/2012 G. Ambrosio and P. Ferracin8

Plans and schedule for QXF G. Ambrosio and P. Ferracin 2nd Joint HiLumi LHC/LARP Annual Meeting November, 2012 Frascati The HiLumi LHC Design Study is included in the High Luminosity LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement Work supported by the US LHC Accelerator Research Program (LARP) through US Department of Energy contracts DE-AC02-07CH11359, DE-AC02-98CH10886, DE-AC02-05CH11231, and DE-AC02-76SF00515

QXF design and prototypes MQXF design: Cable dimension finalized by March 2013 Coil design and parts by December 2013 Integrated plan for short (SQXF) and long (LQXF) prototypes with feedback short  long at each step SQXF1 test starts June 2015 LQXF1 test starts September /11/2012 G. Ambrosio and P. Ferracin10

LQXF length In the present plan the long prototype is as long as LQ (3.3m coils) because this is max length at VMTF. Options were discussed to allow testing a prototype of the final length by 2015 – Extending VMTF and addressing crane limitation – Vertical test at CERN – Horizontal test at FNAL or CERN 15/11/2012 G. Ambrosio and P. Ferracin11

2nd joint HiLumi meeting, 15 Nov M. Sorbi12 Preliminary Studies of Quench Protection for MQXE & MQXF Massimo Sorbi and Giulio Manfreda Milan University & INFN LASA Udine University

2nd joint HiLumi meeting, 15 Nov M. Sorbi13 The agreement between ROXIE and QLASA regarding the hot spot temperature prediction is reasonably good. The MQXF-old design (140 mm) and MQXF-new design (150 mm) presents about the same behavior of the hot spot temperature vs. the delay time & Vqds threshold voltage. The MQXE-HQ magnet presents a slight larger value of hot spot temperature: this is main due to the double effect of lower value of MIITs and larger value of magnetic-energy/conductor-volume The hot spot temperature of MQXF-new design (150 mm) can be considered safe (T < 300 K) with a delay of ms for the effectiveness of quench heater and with Vqds of mV: both these values are feasible if compared to the experience. If the magnets are connected in serie with the same power supply, the calculation has to be re-execute, and by-pass diodes per each magnet are necessary. Conclusion

E. Todesco ISSUES IN QXF PROTECTION E. Todesco With contributions from H. Bajas, H. Felice, T. Salmi, M. Sorbi Frascati, 15 th November 2012 QXF session

E. Todesco Issues in QXF protection - 15 CONCLUSIONS Protection is a very critical aspect for QXF Scheme: little energy can be extracted – we have to work in the scenario of negligible dump resistor Important to test magnets without dump resistor! Hotspot temperature: ~30 ms allowed to quench all magnet to stay below 300 K Main issues: Analysis of time to get above threshold and quench velocity Analysis of propagation from outer to inner Only data for magnet with cored cable will be conclusive Voltage: estimated in a worse case with 8-m-long magnet seem to pose no problem (well within 1kV) Additional verification work is needed to really find the worst case